MCQ
When a $12\,\Omega $ resistor is connected with a moving coil galvanometer then its deflection reduces from $50$ divisions to $10$ divisions. The resistance of the galvanometer is ............. $\Omega $
  • A
    $24$
  • B
    $36$
  • C
    $48$
  • D
    $60$

Answer

${i_g} = \frac{{iS}}{{S + G}}$ $ \Rightarrow $ $10 = \frac{{50 \times 12}}{{12 + G}}$ $ \Rightarrow $ $12 + G = 60$ $ \Rightarrow $ $G = 48\,\Omega $

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